Zabbix

<?php declare(strict_types = 0);

/*

** Copyright (C) 2001-2025 Zabbix SIA

**

** This program is free software: you can redistribute it and/or modify it under the terms of

** the GNU Affero General Public License as published by the Free Software Foundation, version 3.

**

** This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

** without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

** See the GNU Affero General Public License for more details.

**

** You should have received a copy of the GNU Affero General Public License along with this program.

** If not, see <https://www.gnu.org/licenses/>.

**/

​

​

/**

 * A math helper class.

 */

class CMathHelper {

​

    /**

    * Calculate sum of values (overflow safe).

    *

    * @param array $values

    *

    * @return float

    */

    public static function safeSum(array $values): float {

        sort($values, SORT_NUMERIC);

​

        $result = $values[0];

​

        $head = 1;

        $tail = count($values) - 1;

​

        while ($head <= $tail) {

            $result += $values[$result > 0 ? $head++ : $tail--];

        }

​

        return $result;

    }

​

    /**

    * Calculate multiplication of values (overflow safe).

    *

    * @param array $values

    *

    * @return float

    */

    public static function safeMul(array $values): float {

        usort($values, function(float $a, float $b): int {

            return abs($a) <=> abs($b);

        });

​

        $result = $values[0];

​

        $head = 1;

        $tail = count($values) - 1;

​

        while ($head <= $tail) {

            $result *= $values[abs($result) > 1 ? $head++ : $tail--];

        }